(Reuters) - Suspected gang members in El Salvador shot dead seven men and a woman early on Tuesday during a middle school graduation party in Pacific seaport town of Acajutla, police said.
At least four suspected members of local street gangs known as Maras broke into a house in Acajutla, about 52 miles (84 km) southwest of the capital San Salvador, and opened fire on the group without warning, police said.
"This is the most serious incident reported this year," the country's police chief Mauricio Ramirez told reporters.
Among the seven dead men was Cristian Romero, a gang member wanted for murder, authorities said.
The killers wore masks and bulletproof vests, and were armed with guns such as M-16 and AK-47 assault rifles, police said.
A March 2012 truce signed by El Salvador's gangs has slipped this year, sparking an increase in violence.
Year-to-date, homicides in the country are up 56 percent from the first 11 months of last year to 3,425, the government has said.
(Reporting by Nelson Renteria; Editing by Alan Crosby)
